The Ruby Way: Solutions and Techniques in Ruby Programming, Second Edition

8.1. Working with Arrays

Arrays in Ruby are indexed by integers and are zero-based, just like C arrays. There the resemblance ends, however.

A Ruby array is dynamic. It is possible (but not necessary) to specify its size when you create it. After creation, it can grow as needed without any intervention by the programmer.

A Ruby array is heterogeneous in the sense that it can store multiple data types rather than just one type. Actually, it stores object references rather than the objects themselves, except in the case of immediate values such as Fixnums.

An array keeps up with its own length so that we don’t have to waste our time calculating it or keeping an external variable in sync with the array. Iterators also are defined so that, in practice, ...